The Dutch Safety Board released the final report of a serious runway incursion incident at Amsterdam-Schiphol Airport, the Netherlands on July 24, 2004.

Two Boeing 747-400 aircraft were being towed at Amsterdam-Schiphol Airport. PH-CKC was planning to cross runway 04-22. The other, PH-BFU was planning to cross runway 24 at the same time.

The assistant controller cleared erroneously cleared BFU to cross runway 04-22 (“BFU 04-22 crossing approved“). The tow truck driver of did not realise that the clearance was given for another runway and read back: “BFU 04-22 crossing approved. ”

The tow truck driver of CKC noticed the wrong clearance and readback and radioed: “You are not at 04-22 [name].” While the assistant controller was communicating with CKC, the Tower Controller cleared a KLM Boeing 737-300 (PH-BDC) for takeoff from runway 24: “KLM1351 two four cleared for take-off.” At the same time BFU was crossing the same runway at taxiway Sierra 2, located about 1600m from the Boeing 737.

The BFU driver overheard this transmission and questioned his clearance: “BFU was at Sierra 2 24, crossing is approved, eh?” The Tower Controller then cancelled the takeoff clearance for KLM1351 which had only just commenced the takeoff roll.

The Safety Board concluded that an assumed identity and anticipated clearance are the primary causes. The verification process for the clearance of the tow truck driver did not work because of an automatic subconscious “readback” of the runway id was a precondition for a possible false ‘readback’. Also, adverse conditions may have influenced the intensity of the stop bar lights, combined with the reflection of the sun.